Method of re-forming reamers.



H. H. LA VERCOMBE.

METHOD OF RE-FORMING REAMERS.

APPLICATION FILED APILZfi. 19H.

Patented. June 4, 191a.

2 SHEETS-SHEET I.

H. H. LA VERCOMBE.

METHOD OF RE-FORMING REAMEHS.

APPLICATION FILED APR-25. 1917.

2 SHEETS-SHEET 2.

Patented J line 4, 1918.

HARLEY I-I. LA VERCOMBE, 0]? DETROIT, MICHIGAN.

METHOD OF IRE-FORMING- REAMEBS.

Specification of Letters Patent.

Patented June 4, 1918.

Application filed April 25, 1917. Serial No. 164,346.

To all whom it may concern:

Be it known that I, HARLEY H. LA VER- COMBE, a citizen of the United States of America, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Methods of Re-Forming Reamers, of which the following is a specification, reference being had therein to the accompanying drawings.

In the use of reamers of standard type, they rapidly become undersized from wear and necessitate regrinding to smaller sizes unless steps are taken for expanding them. Ordinarily this may be done to a certain extent by endwise pressure but the result is not accurate in the dimensions attained, and presents many difficulties which practically render it of no commercial value.

This invention relates to a method of restoring reamers or the like to original size, the method including steps which are rapidly and accurately carried out in such a manner that the renewed tools are substantially as good as when originally made and whereby the body of the tool is not liable to fracture or distortion.

The invention consists in the matters hereinafter set forth, and more particularly pointed out in the appended claims.

In the drawing,

Figure 1 is a view, largely diagrammatic, showing one means of carrying out the process that forms the invention;

Fig. 2' is a view that shows 9. treated and completed reamer that is the result of the process;

Figs. 3 and 4 show views of another means of obtaining the same result.

In obtaining the desired result, the reamer 1 of standard type with the usual fluted cutting edges or ribs 2, is heated to such a degree that the roots of the respective cutting ribs may be readily compressed. The arrows on Fig. 2 indicate that portion of the ribs which constitutes the roots and when these have been heated to a suilicient degree, they are compressed so as to throw out the cutting face of the tool to at least, and probably beyond its original diameter. This is accomplished by submitting the tool to pressure between the outer face and the inner angle. It may be carried out as indicated in Fig. 1 by the application of a die 12 cooperating with a bed die 13, both being arranged to receive and operate upon teeth that are diametrically opposite and in all instances to compress the root of the tooth and project the latter as indicated at 14 beyond the desired radius whereby it may be ground back to true size. By turning the reamer in the die, the teeth are successively brought to the working face of the die.

Or the tool indicated in Figs. 3 and 4 may be used wherein pairs of cooperating rolls 6 and 7 are arrangedto compress the rib of the reamer by passing the latter therethrough. As a matter of good mechanical detail these rolls may be mounted in an outer frameS in bearing yokes 9 and 10, the latter being adjustable by means of a set screw 11 to adjust the rolls the required distance.

As a result of this method of operation, a reamer which has become considerably undersized may be quickly heated, passed through the dies or rolls and brought nearly to size and then ground to the proper exact dimensions. Because of the accurate pressure which may be brought to bear on each tooth or cutting rib, the ribs are projected evenly during the process with the result that the grinding is readily carried out.

Obviously, changes in the details of carrying out the steps of the process may be changed without departing from the spirit of the invention and I do not care to limit myself to any particular details within the scope of the claim.

What I claim is A method of reforming reamers which consists first, in heating a reamer and then locally compressing each of the several teeth thereof separately between the cutting edge and the root whereby the cutting edges are forced out to the desired diameter of the finished tool.

In testimony whereof I aflix my signature in the presence of two witnesses.

HARLEY H. LA VERCOMBE.

Witnesses:

ANNA M. Donn, O'rro F. BARTHEL.

Copies 0! this patent may be obtained for five cent: each, by addressing the Gommlssiener o2 Eatenta. Washington, D. 0. 

